[v2,1/6] mm: ksm: use more folio api in ksm_might_need_to_copy()
Commit Message
Since ksm only support normal page, no swapout/in for ksm large
folio too, add large folio check in ksm_might_need_to_copy(),
also convert page->index to folio->index as page->index is going away.
Then convert ksm_might_need_to_copy() to use more folio api to save
nine compound_head() calls, short 'address' to reduce max-line-length.
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
---
include/linux/ksm.h | 4 ++--
mm/ksm.c | 39 +++++++++++++++++++++------------------
2 files changed, 23 insertions(+), 20 deletions(-)
@@ -77,7 +77,7 @@ static inline void ksm_exit(struct mm_struct *mm)
* but what if the vma was unmerged while the page was swapped out?
*/
struct page *ksm_might_need_to_copy(struct page *page,
- struct vm_area_struct *vma, unsigned long address);
+ struct vm_area_struct *vma, unsigned long addr);
void rmap_walk_ksm(struct folio *folio, struct rmap_walk_control *rwc);
void folio_migrate_ksm(struct folio *newfolio, struct folio *folio);
@@ -130,7 +130,7 @@ static inline int ksm_madvise(struct vm_area_struct *vma, unsigned long start,
}
static inline struct page *ksm_might_need_to_copy(struct page *page,
- struct vm_area_struct *vma, unsigned long address)
+ struct vm_area_struct *vma, unsigned long addr)
{
return page;
}
@@ -2876,48 +2876,51 @@ void __ksm_exit(struct mm_struct *mm)
}
struct page *ksm_might_need_to_copy(struct page *page,
- struct vm_area_struct *vma, unsigned long address)
+ struct vm_area_struct *vma, unsigned long addr)
{
struct folio *folio = page_folio(page);
struct anon_vma *anon_vma = folio_anon_vma(folio);
- struct page *new_page;
+ struct folio *new_folio;
- if (PageKsm(page)) {
- if (page_stable_node(page) &&
+ if (folio_test_large(folio))
+ return page;
+
+ if (folio_test_ksm(folio)) {
+ if (folio_stable_node(folio) &&
!(ksm_run & KSM_RUN_UNMERGE))
return page; /* no need to copy it */
} else if (!anon_vma) {
return page; /* no need to copy it */
- } else if (page->index == linear_page_index(vma, address) &&
+ } else if (folio->index == linear_page_index(vma, addr) &&
anon_vma->root == vma->anon_vma->root) {
return page; /* still no need to copy it */
}
if (PageHWPoison(page))
return ERR_PTR(-EHWPOISON);
- if (!PageUptodate(page))
+ if (!folio_test_uptodate(folio))
return page; /* let do_swap_page report the error */
- new_page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, address);
- if (new_page &&
- mem_cgroup_charge(page_folio(new_page), vma->vm_mm, GFP_KERNEL)) {
- put_page(new_page);
- new_page = NULL;
+ new_folio = vma_alloc_folio(GFP_HIGHUSER_MOVABLE, 0, vma, addr, false);
+ if (new_folio &&
+ mem_cgroup_charge(new_folio, vma->vm_mm, GFP_KERNEL)) {
+ folio_put(new_folio);
+ new_folio = NULL;
}
- if (new_page) {
- if (copy_mc_user_highpage(new_page, page, address, vma)) {
- put_page(new_page);
+ if (new_folio) {
+ if (copy_mc_user_highpage(&new_folio->page, page, addr, vma)) {
+ folio_put(new_folio);
memory_failure_queue(page_to_pfn(page), 0);
return ERR_PTR(-EHWPOISON);
}
- SetPageDirty(new_page);
- __SetPageUptodate(new_page);
- __SetPageLocked(new_page);
+ folio_set_dirty(new_folio);
+ __folio_mark_uptodate(new_folio);
+ __folio_set_locked(new_folio);
#ifdef CONFIG_SWAP
count_vm_event(KSM_SWPIN_COPY);
#endif
}
- return new_page;
+ return new_folio ? &new_folio->page : NULL;
}
void rmap_walk_ksm(struct folio *folio, struct rmap_walk_control *rwc)